Hostname: page-component-7b7567c8c-fvjsw Total loading time: 0 Render date: 2026-11-12T06:26:44.158Z Has data issue: false hasContentIssue false
  • English
  • Français

A Provisional Reclassification of Granite

Published online by Cambridge University Press:  01 May 2009

F. Chayes
F. Chayes
Affiliation:
Geophysical Laboratory, Carnegie Institution of Washington, Washington 8, D.C.
Get accessRights & Permissions [Opens in a new window]

Abstract

The term “granite” could be usefully reserved for massive or weakly oriented plutonic rocks of colour index less than 20 per cent and quartz content between 20 per cent and 40 per cent by volume. A symbolic classification of rocks meeting these requirements is presented. The various classes are based on the relative proportions of plagioclase and alkali feldspar, and sub-classes based on the ternary dominance ratio quartz-alkali feldsparplagioclase are also proposed. The symbols are simple and easily remembered. A few of the common names now in use are retained for class designations.

Information

Type
Articles
Information
Geological Magazine , Volume 94 , Issue 1 , February 1957, pp. 58 - 68
Copyright
Copyright © Cambridge University Press 1957

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

REFERENCES

Brögger, W. C., 1894. Die eruptivgesteine des kristianiagebiets, II, Vid. Selsk. Skrifter, Kristiania.Google Scholar
Chayes, F., 1952. The finer-grained calcalkaline granites of New England. Journ. Geol., lx, 207–254.CrossRefGoogle Scholar
Chayes, F., 1955. Potash feldspar as a by-product of the biotite-chlorite transformation. Journ. Geol., lxiii, 75–82.CrossRefGoogle Scholar
Goldschmidt, V. M., 1916. Geologisch-petrographische Studien im Hochgebirge des Südlichen Norwegens, no. 4, Vid. Selsk. Skrifter, Kristiania.Google Scholar
Iddings, J. P., 1913. Igneous rocks, vol. ii, J. Wiley and Sons, New York.Google Scholar
Johannsen, A., 1932. A descriptive petrography of the igneous rocks, vol. ii, University of Chicago Press, Chicago.Google Scholar
Lindgren, W., 1900. Granodiorite and other intermediate rocks. Amer. Journ. Sci., 4th ser, ix, 269–282.CrossRefGoogle Scholar
Shand, S. J., 1943. Eruptive rocks, 2nd ed., J. Wiley, New York.Google Scholar
Tuttle, O. F., 1952. Origin of the contrasting mineralogy of extrusive and plutonic salic rocks. Journ. Geol., lx, 107–124.CrossRefGoogle Scholar
Tuttle, O. F., 1954. The granite problem: Evidence from the quartz and feldspar of a Tertiary granite. Geol. Mag., xci, 61–72.CrossRefGoogle Scholar
Warren, C. H., 1913. Petrology of the alkali-granites and porphyries of Quincy and the Blue Hills, Mass. Proc. Amer. Acad. Arts and Sciences, xlix, 203–331.CrossRefGoogle Scholar